Australian dementia rates drop

Dementia rates are on the decline in Australia thanks to a shift towards healthier lifestyles, new research claims.

Dr Stephanie Harrison

According to a study of more than 348,300 older people receiving home care services, the prevalence of dementia fell from 26 per cent in 2005 to 21 per cent in 2014.

For 188,850 older people starting long-term care the dementia dropped from 50 per cent in 2008 to 47 per cent in 2014.

Dementia is a condition that affects the brain and is most common in people over the age of 65.

Researcher conducting the study, which is published in The Journal of Gerontology: Medical Sciences, explained that the decline could linked to measures aimed at improving the physical health of older people.

The positive findings could be linked to national public health measures aimed at improving the overall health of the population, said lead author Dr Stephanie Harrison, a research fellow at the South Australian Health and Medical Research Institute (SAHMRI).

Initiatives to improve risk factors such as smoking rates might also be helping, she said.

“It’s likely there are a combination of factors impacting dementia prevalence so there is probably still room for improvement.”

Dr Harrison warned that the decline in dementia rates is likely to be short lived, with dementia rates expected to rise again because of the ageing population.

Mid-life obesity rates – another risk factor for dementia – are also increasing in Australia, she warned.

There are estimated 436,000 Australians living with dementia and that figure is predicted to rise above 589,000 people by 2028. By 2058 it’s predicted above one million Australians living with dementia.

But there could be a need to reassess current estimates because the prevalence of dementia in Australia might be changing, she said.

International findings

The findings of the large-scale evaluation undertaken by the SAHMRI-based Registry of Older South Australians (ROSA) are consistent with UK and US studies reporting a decline in the prevalence of dementia.

A Harvard School of Public Health study of more than 60,000 people found the chance of developing dementia has fallen by 15 per cent every decade for the last 30 years.

The researchers, who presented the study at an Alzheimer’s Research UK conference in March, said the fall could be linked to the radical decline in smoking rates for men in recent decades.

“With other dementia risk factors, such as obesity and diabetes on the rise, this apparent decline in dementia rates might not continue for long,” Professor Albert Hofman of the Harvard School of Public Health told the conference.